This study investigated the combustion kinetics and spontaneous ignition of sweet sorghum using thermogravimetric analysis and the Frank-Kamenetskii theory. The aim was to determine the proper operating conditions for a direct combustion reactor and predict the safe ambient temperature limits for given silo designs. Oxidative heating rates of 2, 5, and 10 °C/min were set up. Graphical observation shows that combustion was composed of two different stages representing the overlapping processes of pyrolysis and char oxidation, at 131-336 °C and 336-475 °C, respectively. Samples were found to ignite at 215 °C and were extinguished at 433 °C. Different heating rates shifted combustion characteristics to higher temperatures and increased reactivity for ignition and combustion indices up to 12 and 10 times higher. The Friedman method determined the apparent activation energies representing the combustion reaction by 132.91 kJ/mol. Regarding spontaneous ignition, the temperature safe limits were predicted to be 83-84 °C and 84-87 °C for cylindrical and box silos with diameter and height of 15 and 10 m, respectively. Calculations of silos were designed within the limits of certain dimension ratios.
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http://dx.doi.org/10.1186/s40643-022-00536-0 | DOI Listing |
J Phys Chem A
December 2024
Department of Chemistry, University of Hawai'i at Manoa, Honolulu, Hawaii 96822, United States.
Highly energetic boron (B) particles embedded in hydroxyl-terminated polybutadiene (HTPB) thermosetting polymers represent stable solid-state fuel. Laser-heating of levitated B/HTPB and pure HTPB particles in a controlled atmosphere revealed spontaneous ignition of B/HTPB in air, allowing for examination of the exclusive roles of boron. These ignition events are probed via simultaneous spectroscopic diagnostics: Raman and infrared spectroscopy, temporally resolved high-speed optical and infrared cameras, and ultraviolet-visible (UV-vis) spectroscopy.
View Article and Find Full Text PDFACS Omega
October 2024
Chair of Thermal Process Engineering, University of Duisburg-Essen, Duisburg 47057, Germany.
Porous boron nitrides possess beneficial properties such as high thermal and chemical stability which are critical for applications in adsorption processes. In order to assess possible fields of applications, trace-level adsorption isotherms of different hydrocarbons on two synthesized porous boron nitrides and two commercial activated carbons are compared. By normalizing the adsorptive loadings on the micropore surface area, superior adsorption performances of the BN materials on polar and aromatic adsorptives with up to 50% higher loadings compared to the activated carbons can be shown.
View Article and Find Full Text PDFEmerg Med Int
September 2024
Emergency Department Shengjing Hospital of China Medical University, Shenyang, Liaoning, China.
Introduction: Over the years, numerous studies have suggested the occurrence of a peculiar phenomenon known as "CPRIC" during the revival process. The revelation of this phenomenon has ignited widespread discussion and investigation, yet many enigmas remain unsolved. This study describes the case of a 52-year-old man diagnosed with acute anterior myocardial infarction, who experienced ventricular fibrillation while awaiting further treatment.
View Article and Find Full Text PDFMil Med
August 2024
Perelman School of Medicine, University of Pennsylvania; Division of Trauma, Surgical Care, and Emergency Surgery, Philadelphia, PA 19104, USA.
Introduction: Solid metals may create a variety of injuries. White phosphorous (WP) is a metal that causes both caustic and thermal injuries. Because of its broad use in munitions and smoke screens during conflicts and wars, all military clinicians should be competent at WP injury identification and acute therapy, as well as long-term consequence recognition.
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August 2024
School of Emergency Management and Safety Engineering, North China University of Science and Technology, Tangshan, Hebei 063210, China.
The stagnant water above the coal seam flows into the goaf, causing the goaf coal to be soaked by water for a long time. Compared with dry raw coal, water-soaked coal has a stronger tendency for spontaneous combustion, which poses a serious threat to mining operators. To unravel the impact of water immersion on coal's self-heating properties, an investigation was conducted employing techniques such as simultaneous thermogravimetric analysis/differential scanning calorimetry (TG/DSC), scanning electron microscopy (SEM), low-temperature nitrogen adsorption based on the BET theory, and Fourier transform infrared spectroscopy (FTIR).
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